(01-16-2019, 03:24 PM)73pony Wrote: I do believe that the last connection point is in the engine bay at the firewall. I do not think there are any connections IE O-Rings inside the car.

Confirm this. Hoses should be O K ( see note below ) but new O'rings ( generally light green, Viton material ) will need to go on all end connections. The last component is the T X valve on the engine side of the firewall. All under dash items are metallic Be aware also that there is a vacuum controlled tap in the inlet heater hose. It is actuated from inside and will restrict the hot water flow to the heater core when the A / C is turned on. You will see all this in a vacuum schematic diagram. Worth a look before you start.

I am in Australia and regs require flexible lines with nylon tube to avoid permeation of gas through old style rubber hoses. You may want to check this out with an A / C installation service agent so you don't have to do it twice. Dig out some Youtube videos on the procedure to run a full vacuum test before you try to re - gas it. Mine looked all good but the T X valve was jammed closed.
Have fun.
PKJ